Speedo drive gear

Second Nylon gear that connects with cable is not spinning. Covered in brown rusty/crusty looking grease.
First nylon gear, teeth stripped.
Not working so swapped out with working one.

Is it rust in the grease? Bearing grease ? Is moisture coming down the cable into gears.?

If I clean out speedo gear and refill with white grease once a year, will it prevent gear from jamming up, and last longer?

Should I lube front axle with anything while I'm down there?

 

What scooter ?

 

Zip

 

And, is the supplied ready lubed speedo gear, reacting with added lube?
Does the old lube and any new lube chemically react over time and go hard?
? ??

 

I know it's not bearing grease because they are sealed.

 

Or, do I have too much time on my hands ?

Also is it just the seal degrading and collecting dirt into the hub?

 

Just clean and grease/ lube cable with oil.